I prefer storing frozen sections unfixed.  Cut and air dry for 1 hour and
then wrap individually in foil and store in plastic zip bags in a -70 d C
freezer.  When you are ready to use them either take a jar of fixative to
the freezer with you and take them out individually and put directly into 4
d C fixative or take them out and put into a dessicator for 15 min. or so
until they come to room temp before unwrapping and fixing.
Patsy Ruegg  

		-----Original Message-----
		From:	vandeplas@aurion.nl [mailto:vandeplas@aurion.nl]
		Sent:	Wednesday, June 09, 1999 4:21 PM
		To:	Histonet@Pathology.swmed.edu
		Subject:	Re: Storage of frozen sections

		Jennifer wrote:
		 Good Morning Histonetters!  Does anyone have experience
with storage of
		sectioned frozen tissue???  In the past I have only
sectioned tissue that I
		would immunostain immediately.  Currently my boss is
concerned with losing
		tissue each time that I would re-trim a block; thus he
prefers that I section
		approximately 20 slides at a time per block and store the
slides for subsequent
		immunohistochemical staining (to be performed ASAP).  I
consulted one book which
		suggested that fixed slides could be stored at -70 C if
dessicated!  Any
		opinions or experience in this matter???  Thank you very
much in advance!
		-----------------------------------------------
		Dear Jennifer,
		The following is not my answer, but a previous answer of one
of the fellow
		histonetters to a similar question.


		We have the best luck with the black plastic boxes (25 slide
capacity)
		with a small nylon process bag or lens paper containing
silica gel to absorb
		moisture when you bring sections back to room temperature.
We also
		wrap tape around outside to seal box, this may be overkill,
but it
		provides label.  Avoid calcium chloride, anhydrous as a
substitute
		for silica gel, Drierite (sp?) is also a problem since these
exfoliate fine
		particles that float around, could deposit on sections.
silica gel stays intact
		and is reused for a long time.
		Store sections fixed, air dried, in -80C freezer, then bring
them
		to room temperature BEFORE opening the lid, 20 - 30 minutes.
		also stored slides in plastic slide mailers with snap lids,
wrapped
		in foil, either in a plastic zip lock, or two mailers per
black slide
		box with silica gel, you can remove one box and keep other
for another
		day.
		These are frozen sections, have stored unfixed frozens in
slide mailers with
		success, but only for a few weeks.  Fixed sections store for
longer times


		Regards, Peter

		========================================
		Peter van de Plas
		AURION
		Costerweg 5
		6702 AA Wageningen
		The Netherlands
		phone: (31)-317-497676
		fax: (31)-317-415955
		http://www.aurion.nl